Lighting unit



June 1, 1937. A. F. H. DAVIS 2,082,687

LIGHTING UNIT Filed Dec. 10, 1936 3 Sheets-Sheet l INVENTOR.

k 145mm fin-Tween bQ-w/ 0 W5 ATTORNEY.

June 1, 1937. I DAVIS 2,082,687

LIGHTING UNIT Filed Dec. 10, 1936 3 SheetsSheet 2 F'IG.3

- INVENTOR. 145N639 fisfirwaoa flax 2y Dav/5 BY JQLW Q, W

ATTORNEY.

June 1, 1937. A. F. H. DAVIS LIGHTING UNIT Filed Dec. 10, 1936 3Sheets-Sheet 3 F'lG.4

. INVENTOR. lam-e flszrwoaa /7'ENRY fin v/s Ul/WZ 2m Patented June 1,1937' puns!) STATES PATENT OFFICE LIGHTING UNIT Application December 10,1936, Serial No. 115.116

6 (Claims.

My invention has for its principal objectto provide a, lighting unitwhich will spray the light rays, emitted by a source of light such as anelectric bulb, over a fan-shaped area on -a desk or table with a highdegree of emciency.

A further object is to provide a construction which will shield thelight source entirely from the eye of a person seated at a desk ortable, while at the same time, redirecting the light rays over the saidfan-shaped area in a highly efflcient manner.

A further object is to provide one or more supplemental and redirectingreflectors where a greater degree of intensity is desired.

My means of accomplishing the foregoing ob- J'ects may be more fullycomprehended by have ing reference to the accompanying drawings, whichare hereunto annexed and are a part of this specification in which:

20, Fig. l is a side view of my invention applied to a portable or tablelamp, portions of the structure being shown in section;

Fig. 2 is a fragmentary detail view showing the manner of supporting anauxiliary reflector;

25 Fig. 3 is a view similar to Fig. 1 showing different forms ofsupplemental reflectors.

Fig. 4 is a, top plan view of Fig. 1 showing diagrammatically thecontour of the light raysas they strike the top of a desk.

3 Similar reference numerals refer to similar parts throughout theentire specification.

For the purpose of illustration, I have shown my invention in connectionwith a portable or table lamp, but this is solely to shows. concrete 3embodiment of my invention, for I do not wish to be understood aslimiting myself in any particular to the specific structures shown anddescribed, for many changes may be made in the application and use of myinvention regardless of 40 the manner in which the light source issupported.

As shown in the drawings, a light source I is mounted in a socket 2carried by a tube 3 through which the electric conductors (not shown)may I .1 be carried to the socket in the usual manner. The socket isenclosed in a cylindrical casing or pedestal 4 which is mounted upon abase 5 in the interior of which is a metal weight 6 which operates tomaintain the lamp in proper 50 position. The weight is held in place bymeans of a nut I mounted upon the lower end. of the tube 3.

The casing l is flared outwardly adjacent the skirt of the lamp I as at8. Inside of the flared 55 portion 8 of the casing 4, I may provide asupplemental reflector. 9 which receives the light rays from the sourceand directs them upwardly so that they-will impinge upon a reflectingsurface of a concave reflector member ID, of larger diameter than thereflector 9, the center of the 5 concave member l0 being eccentric tothe-center of the light source. The reflector I0 is carried by areflector tube II which extends around its exterior as clearly seen inFig. 1,

its lower end being secured in position to lo the casing 4. Thissupplemental reflector 9 is held in place by means of a stud 12 mountedin the end l3 of the reflector tube II, a nut l4 serving to hold thesupplemental reflector 9 firmly in position. 15

As clearly shown in the drawings, reflector i0 is a surface ofrevolution generated about its axis, said axis being parallel to theaxis of the smaller reflector and falling outside said reflector. It isobvious however that the surface of the reflector may be somewhatmodified to give it a more ornamental appearance without departing; fromthe spirit of the invention.

Ventilating openings l5 and it are provided in the casing 4, as shown,they are two in number though it should be perfectly obvious that anynumber requisite to provide perfect ventilation may be employed. Asimilar vent I1 is formed adjacent the lower end of the reflector tubeII.

It will be apparent from the foregoing description that the direct raysemitted upwardly from the source will strike the concave reflectingsurface of the member In whence they will be reflected, and redirectedas clearly indicated by Y the arrows shown in the drawings. The otherrays emitted by the source will impinge upon the supplemental reflector9 from which they will be reflected onto the reflecting surface of theconcave reflector member ID where they will be re-reflected andredirected as indicated by the arrows.

The result of this construction is that the light rays as clearly shownby the arrows in Fig. 4, are spread out upon the desk or table 29 over afan-shaped area in the front of the lamp and by making. the reflectingsurface of the concave reflector l0 and of the supplemental reflector 9of the most efficient quality, a very high degree of efficiency isattained and a very satisfactory illumination of the fan-shaped area infront of the lamp follows.

It may, in some cases, be found desirable to furnish a redirectingreflector iii. In the drawings I have shown such a reflector i8 securedto two arms 19 and 20 of a U-shaped member,

the connecting portion 2| of which is attached to the casing 4 by meansof rivets 22, or in any be found desirable.

' by a coil spring 24 which is coiled around the skirt of the lamp orthe reflecting surface may be on the lamp bulb itself or the reflector-23' may be entirely omitted and the inner surface 25 of the flaredportion 8 may be provided with a coating of suitable reflectingmaterial.

It may, in some instances, be found desirable to provide a separatereflector 26 mounted inside of the concave member Hi. When this is done,obviously the concave member ID will not have its inner surface coatedwith reflecting material. This construction has the added feature, ofproviding for a space intermediate the concave member l0 and thereflector 26 which can be utilized for ventilating purposes which willaid in keeping the concave member I ll cool.

It will be apparent from the foregoing description, that owingto thefact that the perimeter 21 of the concave reflecting member I0 extendsbelow the upper edge 28 of the flared portion 8 of the casing 4 that itis impossible for any direct rays of light to strike the eye of theobserver or of a person seated at the desk, while by mounting theconcave reflector eccentric to the center of the light source, asclearly seen in the drawings, I am able to provide for the 11-lumination of a fan-shaped area directly in front of the lamp. In thismanner, I obtain a high degree of eye comfort without a correspondingloss in lumens due to absorption in shields commonly employed for thispurpose.

Having described my invention, what I regard as new and desire to secureby Letters Patent is:

1. A stand lamp comprising a pedestal, a light source at the topthereof, a'reflector surrounding said light source to direct thelightrays upwardly, an upper concave reflector separate from and oflarger diameter than the first said reflector supported above the lightsource and smaller reflector so as to receive the upwardly directedlight rays and project them fan-shaped at one side of the pedestal,said'upper reflector being constructed substantially as a surface ofrevolution generated about its axis with said axis positionedsubstantially parallel to the axis ofthe smaller reflector and to oneside thereof.

2. A stand lamp comprising a pedestal, a light source at the topthereof, a reflector surrounding said light source to direct the lightrays upwardly, an upper concave reflector of larger diameter than thefirst said reflector supported above the light source and smallerreflector so as to receive the upwardly directed light rays and projectthem fan-shaped at one side of. the pedestal, said upper reflector beingconstructed substantially as a surface of revolution generated about itsaxis with said axis positioned substantially parallel to the axis of thesmaller reflector and to one side thereof, said upper reflector havinga'lower edge extending below the upper edge of the smaller reflector.

3. A stand lamp comprising a pedestal, a light source at the topthereof, a reflector surrounding said light source to direct the lightrays upwardly, an upper concave reflector of larger diameter than thefirst said reflector supported above the light source and smallerreflector so as .to receive the upwardly directed light rays and projectthem fan shaped at one side of the pedestal, said upper reflector beingconstructed substantially as a surface of revolution generated about itsaxis with said axis positioned substantially parallel to the axis of thesmaller reflector and to one side thereof and a tube secured to thepedestal adjacent the smaller reflector to support the larger reflector,there being ventilating apertures in said pedestal and tube to cool saidreflectors.

4. A stand lamp comprising a pedestal, a light source at the topthereof, a reflector surrounding said light source to direct the lightrays upwardly, an upper concave reflector separate from and of largerdiameter than the first said reflector supported above the light sourceand smaller reflector so as to receive the upwardly directed light raysand project them fan-shaped at one side of the pedestal, said upperreflector being constructed substantially as a surface of revolutiongenerated about its axis with said axis positioned substantiallyparallel to the axis of the smaller reflector and to one side thereof,the

eccentrically mounted peripheries of the two reflectors beingsubstantially aligned at one point. 5. A stand lamp comprising apedestal, a light source at the top thereof, a reflector surroundingsaid light source to direct the light rays upward- 1y. an upper concavereflector of larger diameter than the first said reflector supportedabove the light source and smaller reflector so as to receive theupwardly directed light rays and project them fan-shaped at one side ofthe pedestal, said upper reflector being constructed substantially as asurface of revolution generated about its axis with said axis positionedsubstantially parallel to the axis of the smaller reflector and to oneside thereof, and a redirecting reflector secured to the pedestal belowthe smaller reflector to redirect reflected rays on to the illuminatedarea atone side of the pedestal.

6. A stand lamp comprising a pedestal casing, a socket mounted in saidcasing, a source of light in said socket, said casing having an upwardlyand outwardly flaring reflector which surrounds said light source, aweighted base for said casing, a concave reflector mounted above saidlight source, the perimeter of which extends below the upper edge of theflaring reflector, the axis of said concave reflector being parallel tothe axis of the flaring reflector and substantially outside thereof, atube for supporting said'concave reflector and secured to said casing,there being ventilating apertures in said tube and casing, and aredirecting reflector secured to the outside of said casing below theflaring reflector.

